STOCK 5.7 Vortec swap
 

This may or may not have been discussed before, idk I cant really find the answer I'm looking for so MAYBE not. I have a bone Stock 1991 3.1 RS with 148k miles. Haven't had the car for long but Im not looking to keep the V6 that's in it, I just don't like the fact that it can't even get out of it's own way... With that said I have read post after post of people taking a 350, putting vortec heads, Holly 650 or larger Double Pump carb, mild cam, and RPM air gap intake sitting in front of a 700R4 and successfully seeing 23 to 25 mpg out of it. I'm curious to know if anyone has taken a BONE STOCK vortec 5.7, and swapping the intake to except a carb and seen the same results or better?

I agree, even the TPI350 that came in the 1992 struggled to get 25MPG highway. The vortech heads are nice for HP but gain next to nothing in miles per gallon. Their claim to fame is they will allow high end hp without hurting low end torque.

Keep in mind that a carb can be tuned to run lean which kills emission, power and the engine itself. Also there is a term call hypermiling which is a way of driving to get better mileage. If you do that then maybe you have a chance. I would rather chew glass.

:icon_crackup: I'm with you on that,I don't drive a Prius for a reason.

I have a 96 c3500 with a 5.7 vortec and I am looking to get some more power out of it. I’m looking at an Edelbrock top end kit (EDL-2038) I was wondering if the mods are possible on a vortec block. And are the vortec blocks the same as a gen 1 350? Kodi

You are in the third gen Camaro forum piggybacking an old thread, you should post a new thread of your own in the proper forum or at least the lounge where most anything goes.
Better chance to get what you're looking for that way.
Try here: Intake, Headers, and Exhaust - Camaro Forums - Chevy Camaro Enthusiast Forum